<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <title>Document</title>
  </head>
  <body>
    <button>123</button>
    <script>
      const ws = new WebSocket("ws://localhost:8080");
      ws.onopen = () => {
        console.log("open");
        ws.send("hello");
      };
      ws.onmessage = (e) => {
        console.log(e.data);
      };
      document.querySelector("button").addEventListener("click", () => {
        ws.send("hello");
      });
    </script>
  </body>
</html>
